JP6033908B2 - V belt type continuously variable transmission - Google Patents

Description

  The present invention relates to a V-belt continuously variable transmission that continuously transmits and transmits power of an internal combustion engine mounted on a vehicle.

In the V-belt type continuously variable transmission, the drive pulley provided on the drive shaft has a movable drive pulley half supported by the drive shaft so that relative rotation is restricted and slidable in the axial direction according to the engine speed. Power is transmitted by rotating around a V-belt between a fixed drive pulley half that is slid in the direction and fixed to the drive shaft.
In general, a centrifugal weight is used to slide the movable driving pulley half in the axial direction according to the engine speed (see, for example, Patent Document 1).

JP 2010-236647 A

  In the V-belt type continuously variable transmission disclosed in Patent Document 1, a centrifugal weight is provided between a movable drive pulley half and a tapered back surface on the opposite side of the fixed drive pulley half so as to be sandwiched between guide plates. Depending on the number of rotations, the movable drive pulley half approaches and separates from the fixed drive pulley half by the centrifugal weight guided by the guide plate and moving in the radial direction, and the winding diameter of the V belt on the drive pulley changes. At the same time, when the winding diameter of the driven pulley is changed, the transmission gear ratio is automatically changed and the continuously variable transmission is performed.

  The driven shaft on which the driven pulley is provided is provided with a centrifugal clutch mechanism between the driven pulley and power is transmitted to the driving wheel at a predetermined engine speed or higher.

  The V-belt is always sandwiched between the fixed driving pulley half and the movable driving pulley half, and the V-belt wound around the driving pulley that is rotated by the power of the internal combustion engine is always connected to the driving pulley. The belt is circulated by slight friction, and the driven pulley around which the V belt is wound is always rotating with the rotation of the V belt.

  When the centrifugal clutch mechanism is connected at a predetermined engine speed or higher, the rotation of the driven pulley is transmitted to the drive wheels. During idle operation until the predetermined engine speed is reached, the power of the internal combustion engine is driven by the V belt. The driven pulley is also rotated, and the load caused by the rotating motion of the V-belt and the driven pulley during the idle operation reduces the fuel consumption.

  The present invention has been made in view of the above points, and the object of the present invention is to provide a V-belt continuously variable transmission that can reduce the load during idling and improve fuel efficiency.

In order to achieve the above object, the invention according to claim 1
A V-belt is bridged between a drive pulley provided on a drive shaft to which power of an in-vehicle internal combustion engine is transmitted and a driven pulley provided on a driven shaft to which power is transmitted to a wheel. A fixed drive pulley half in which a movable drive pulley half that is supported by a drive shaft so that relative rotation is restricted and is slidable in the axial direction slides in the axial direction according to the engine speed and is fixed to the drive shaft. In a V-belt type continuously variable transmission in which opposed taper surfaces facing each other rotate around the V-belt and transmit power to the driven shaft,
A biasing means for biasing the movable drive pulley half with respect to the fixed drive pulley half is provided , the biasing means is a conical coil spring, and the fixed drive pulley half is opposed to A conical portion forming a tapered surface has a cylindrical portion extending from the inner peripheral end of the conical portion to the opposite side of the movable drive pulley half in the axial direction, and an end opposite to the conical portion of the cylindrical portion is the inner side And a conical coil spring is inserted into the cylindrical portion of the fixed drive pulley half, and the bottom wall portion and the movable drive pulley half are provided with a bottom wall portion extending to the drive shaft and fixed to the drive shaft. It is characterized by being interposed between .

According to this configuration, the urging means for urging the movable drive pulley half with respect to the fixed drive pulley half is provided. On the other hand, the movable drive pulley half is moved away from the movable drive pulley half so that the V drive belt is not sandwiched between the movable drive pulley half and the fixed drive pulley half. It can be transmitted only, and the rotation of the V-belt and the driven pulley can be prevented, and the load during idling can be reduced and the fuel consumption can be improved.
Since the coil spring is inserted into the cylindrical portion of the fixed drive pulley half and interposed between the bottom wall portion and the movable drive pulley half, the coil spring has an opposing tapered surface of the fixed drive pulley half. It is compactly disposed in a cylindrical portion that overlaps the conical portion to be formed in the axial direction, and the axial width of the drive pulley can be kept small.
Further, by using a conical coil spring as the coil spring, the expansion / contraction stroke can be increased by overlapping in the axial direction when the spring is compressed, and the axial width of the drive pulley can be suppressed small.

The invention according to claim 2
A V-belt is bridged between a drive pulley provided on a drive shaft to which power of an in-vehicle internal combustion engine is transmitted and a driven pulley provided on a driven shaft to which power is transmitted to a wheel. A fixed drive pulley half in which a movable drive pulley half that is supported by a drive shaft so that relative rotation is restricted and is slidable in the axial direction slides in the axial direction according to the engine speed and is fixed to the drive shaft. In a V-belt type continuously variable transmission in which opposed taper surfaces facing each other rotate around the V-belt and transmit power to the driven shaft,
A biasing means for biasing the movable drive pulley half with respect to the fixed drive pulley half is provided, the biasing means is a coil spring, and the fixed drive pulley half has an opposing taper. A cylindrical portion extending from the inner peripheral end of the conical portion to the opposite side of the movable drive pulley half in the axial direction, and an end opposite to the conical portion of the cylindrical portion on the inside. A bottom wall portion that extends and is fixed to the drive shaft, and the coil spring is inserted into the cylindrical portion of the fixed drive pulley half, and between the bottom wall portion and the movable drive pulley half. The movable drive pulley half is fitted on a slide sleeve that is supported by the drive shaft so as to be slidable in the axial direction with relative rotation restricted, and the movable support sleeve is movable. Extending axially from the drive pulley half toward the fixed drive pulley half Is bearing on the outer periphery of the detecting portion is fitted, when the engine speed is low, characterized in that the bearing is located between the movable driving pulley half body and the stationary driving pulley halves.

  According to this configuration, when the engine speed is small, the V-belt is fitted on the sliding support sleeve without being sandwiched between the stationary driving pulley half and the movable driving pulley half separated by the coil spring on the driving pulley side. Therefore, the friction between the rotating drive shaft and the V-belt can be suppressed, and the fuel consumption can be further improved.

In the above configuration,
The coil spring may be interposed between the bottom wall portion of the fixed drive pulley half and the inner race of the bearing.

  According to this configuration, the coil spring is sandwiched between the bottom wall portion of the fixed drive pulley half and the inner race of the bearing and rotates with the drive shaft. Therefore, the rotation of the fixed drive pulley half is performed when the engine speed is low. Can be reliably prevented from being transmitted to the V-belt supported by the outer race of the bearing.

In the above configuration,
When the engine speed increases, the bearing is accommodated inside the cylindrical portion of the fixed drive pulley half by moving the movable drive pulley half in the direction approaching the fixed drive pulley half. Good.

  According to this configuration, the axial width of the drive pulley can be suppressed as small as possible while ensuring the moving distance of the movable drive pulley half.

The present invention greatly separates the movable drive pulley half from the fixed drive pulley half by a conical coil spring that biases the movable drive pulley half away from the fixed drive pulley half, such as during idle operation. Thus, by preventing the movable drive pulley half from sandwiching the V-belt with the fixed drive pulley half, the power of the internal combustion engine is transmitted only to the drive shaft, and the V-belt rotating motion and the driven pulley are transmitted. Thus, it is possible to reduce the load during idling and improve fuel efficiency.
Since the coil spring is inserted into the cylindrical portion of the fixed drive pulley half and interposed between the bottom wall portion and the movable drive pulley half, the coil spring has an opposing tapered surface of the fixed drive pulley half. It is compactly disposed in a cylindrical portion that overlaps the conical portion to be formed in the axial direction, and the axial width of the drive pulley can be kept small.
Further, by using a conical coil spring as the coil spring, the expansion / contraction stroke can be increased by overlapping in the axial direction when the spring is compressed, and the axial width of the drive pulley can be suppressed small.

1 is an overall side view of a motorcycle according to an embodiment of the present invention. It is the whole side view which removed the transmission case cover of the power unit. It is the perspective view which removed the transmission case cover of the power unit, and a part was omitted. It is a longitudinal cross-sectional view (IV-IV line sectional view of FIG. 2) of the same power unit. FIG. 5 is a cross-sectional view (cross-sectional view taken along the line V-V in FIG. 2) on the drive pulley side of the V-belt type continuously variable transmission when the engine speed is small. FIG. 6 is a cross-sectional view (cross-sectional view taken along line VI-VI in FIG. 2) on the driven pulley side of the V-belt continuously variable transmission when the engine speed is small. It is a cross-sectional view on the drive pulley side of the same V-belt type continuously variable transmission when the engine speed is large. It is a cross-sectional view on the driven pulley side of the same V-belt type continuously variable transmission when the engine speed is high.

Hereinafter, an embodiment according to the present invention will be described with reference to FIGS.
FIG. 1 is a side view of a motorcycle 1 that is a straddle-type vehicle according to an embodiment to which the present invention is applied.
In the description of the present specification, the front, rear, left, and right directions are based on a normal standard in which the straight traveling direction of the motorcycle 1 according to the present embodiment is the front. In the drawings, FR is the front and LH is the left And RH indicates the right side.

The vehicle body front portion 1f and the vehicle body rear portion 1r are connected via a low floor portion 1c, and the vehicle body frame forming the skeleton of the vehicle body is generally composed of the down tube 3 and the main pipe 4.
That is, the down tube 3 extends downward from the head pipe 2 at the front part 1f of the vehicle body, the down tube 3 is bent horizontally at the lower end and extends rearward under the floor 1c, and a pair of left and right main pipes 4 at the rear end. The main pipe 4 rises obliquely rearward from the connecting portion, bends horizontally at a predetermined height, and extends rearward.

A seat 6 is disposed above the main pipe 4.
On the other hand, at the vehicle body front portion 1f, a handle 11 is provided above and supported by the head pipe 2, a front fork 12 extends downward, and a front wheel 13 is supported at the lower end thereof.

A bracket 15 protrudes rearward from the front lower end of the main pipe 4, and a link member 16 is connected to the bracket 15.
The power unit 20 is a single-cylinder four-stroke air-cooled internal combustion engine 30 at the front, and the cylinder block 32 is inclined forward to a substantially horizontal state, and forward from the lower end of the crankcase 31. An end portion of the protruding hanger bracket 18 is connected to the link member 16 via a pivot shaft 19 and a power unit 20 is connected and supported so as to be swingable up and down.

The power unit 20 includes a V-belt continuously variable transmission 60 extending rearward from the internal combustion engine 30, and a rear wheel 21 is provided on a rear axle 125, which is an output shaft of a reduction gear mechanism 120 provided at a rear portion thereof ( (See FIG. 2).
A rear cushion 22 is interposed between a support bracket 29 erected at the rear portion of the power unit 20 having the reduction gear mechanism 120 and the rear portion of the main pipe 4 (see FIG. 1).

In the upper part of the power unit 20, the intake pipe 23 extends from the upper part of the cylinder head 33 that is largely inclined forward of the internal combustion engine 30 and curves backward, and the air cleaner above the V-belt type continuously variable transmission 60 through the throttle body 25. Has reached 26.
On the other hand, the exhaust pipe 27 extending downward from the lower portion of the cylinder head 33 is bent rearward, is biased to the right and extends rearward, and is connected to the muffler 28 on the right side of the rear wheel 21.

The front part 1f of the vehicle body is covered from the front and the back by the front cover 9a and the leg shield 9b, and the lower part is covered from the front to the left and right by the front lower cover 9c, and the center part of the handle 11 is covered by the handle cover 9d.
The floor portion 1c is covered with a side cover 9e, and the vehicle body rear portion 1r is covered with a body cover 10 from the left and right sides.

  2 is an overall side view of the power unit 20 with the transmission case cover 61 removed, FIG. 3 is a perspective view with the transmission case cover 61 of the power unit 20 removed and a portion omitted, and FIG. 4 is a longitudinal sectional view of the power unit 20 ( It is the IV-IV sectional view taken on the line of FIG.

Referring to FIG. 4, in the internal combustion engine 30, a connecting rod 43 connects a piston 42 that reciprocates in a cylinder liner 32 l of a cylinder block 32 and a crank pin 40 p of a crankshaft 40.
The crankshaft 40 has an integral structure in which the crank pins 40p are connected to the crank webs of the left crankshaft 40L and the right crankshaft 40R.

  The crankcase 31 is configured by combining a left crankcase 31L and a right crankcase 31R which are divided into left and right parts. The right crankcase 31R forms a half of a crankcase portion, and the left crankcase 31L is a front crankcase 31L. The portion serves as a half of the crankcase portion, and also serves as a transmission case that extends rearward and accommodates a long V-belt continuously variable transmission 60 in the front-rear direction.

  The front left and right open surfaces of the transmission case (left crankcase) 31L are covered with a transmission case cover 61, and a transmission chamber 60C in which the V-belt type continuously variable transmission 60 is housed is formed. The right open surface is covered with a reduction gear cover 121, and a reduction gear chamber 120C in which the reduction gear mechanism 120 is housed is formed.

  Referring to FIG. 4, in a so-called crankcase formed by the combination of the front portion of left crankcase 31L and right crankcase 31R, crankshaft 40 is attached to each side wall of left and right crankcases 31L, 31R on left and right main bearings 41, 41 is rotatably supported via 41.

  A cam chain drive sprocket 44 and an oil pump drive gear 45 are fitted on the shaft portion of the right crankshaft 40R extending in the right horizontal direction, and an AC generator 46 is provided at the right end. The AC generator 46 is provided with an ACG cover 47. Covered with.

  The four-cycle internal combustion engine 30 employs an SOHC type valve system. A valve mechanism 50 is provided in the cylinder head cover 34, and a cam chain 51 that transmits power to the valve mechanism 50 includes a camshaft 53. Between the right crankshaft 40R and a cam chain chamber 52 that covers the cam chain 51 is provided in communication with the right crankcase 31R, the cylinder block 32, and the cylinder head 33 (see FIG. 4). ).

  That is, the cam chain 51 is connected to the cam chain chamber 52 between the cam chain driven sprocket 56 fitted to the right end of the cam shaft 53 oriented in the horizontal direction and the cam chain drive sprocket 44 fitted to the crankshaft 40. It is passed through the inside.

The rollers at the ends of the intake rocker arm 54 and the exhaust rocker arm 55 are in contact with the intake cam surface and the exhaust cam surface of the camshaft 53.
In the cylinder head 33, a spark plug 36 is inserted from the side opposite to the cam chain chamber 52 (left side) toward the combustion chamber 35 (see FIGS. 3 and 4).

With reference to FIGS. 3 and 4, the cylinder block 32 and the cylinder head 33 are covered with a shroud 37.
A portion of the shroud 37 covering the cylinder block 32 and the left side of the cylinder head 33 is formed with an air duct portion 37b that gradually bulges leftward from the front portion to the rear portion.
The rear portion of the air duct portion 37b forms an opening 37bh toward the rear V-belt type continuously variable transmission 60.

  Referring to FIG. 5 which is a transverse sectional view of the drive belt 70 side of the V-belt type continuously variable transmission 60, the shaft portion extending leftward of the left crankshaft 40L is fitted to the side wall of the left crankcase 31L. Journal portion 40a in the vicinity of the crank web that is pivotally supported through the main bearing 41 and sealed by the seal member 48, and an extended shaft portion 40b that is reduced in diameter through a step from the journal portion 40a and extends to the left. And a spline shaft portion 40c that extends further leftward from the extension shaft portion 40b and has a spline groove formed on the outer periphery thereof, and a male screw portion 40d that is an end protruding from the spline shaft portion 40c.

In the V-belt type continuously variable transmission 60 on the left side of the power unit 20, the drive pulley 70 provided on the shaft portion extending to the left of the left crankshaft 40L is fixedly driven to be splined to the spline shaft portion 40c of the left crankshaft 40L. A pulley half 71 and a movable drive pulley half 72 provided on the extended shaft portion 40b so as to be opposed to the fixed drive pulley half 71 on the right side and slidable in the axial direction.
The fixed drive pulley half 71 and the movable drive pulley half 72 have conical portions 71c, 72c that face each other and form opposed tapered surfaces 71f, 72f that sandwich the V belt 75 therebetween.

The fixed drive pulley half 71 includes a cylindrical portion 71s extending from the inner peripheral end of the conical portion 71c to the opposite side of the movable drive pulley 72 in the axial direction, and an end opposite to the conical portion 71c of the cylindrical portion 71s. The bottom wall 71b has a bottom wall portion 71b extending inwardly, and the bottom wall portion 71b is spline-fitted to the spline shaft portion 40c of the left crankshaft 40L.
The inner diameter of the cylindrical portion 71s of the fixed drive pulley half 71 is sufficiently larger than the outer diameter of the shaft portion of the left crankshaft 40L.

The movable drive pulley half 72 facing the right side of the fixed drive pulley half 71 is provided with a cylindrical portion 72s extending from the inner peripheral end of the conical portion 72c to the opposite side of the fixed drive pulley half 71 in the axial direction.
Between the curved back surface (right side) behind the conical portion 72c of the movable drive pulley half 72 and the guide plate 63 that is pivotally supported by the extension shaft portion 40b of the left crankshaft 40L and fixed in contact with the journal portion 40a. A plurality of centrifugal weights 62 are disposed so as to be movable in the radial direction.

  A guide plate 63 is inserted into the extended shaft portion 40b projecting leftward from the seal member 48 of the left crankshaft 40L to contact the stepped portion with the journal portion 40a, and then a cylindrical collar member 64 is inserted. The fixed drive pulley half 71 contacts the inner peripheral base of the guide plate 63 and then contacts the end of the collar member 64 by spline fitting the bottom wall 71b to the spline shaft 40c. The inner peripheral base portion of the conical substrate 65b to which a large number of blades 65p are attached is spline-fitted to the spline shaft portion 40c and abuts against the bottom wall portion 71b of the fixed drive pulley half 71, and then the nut 67 through the washer 66 Are screwed into the male screw portion 40d and tightened.

  Therefore, the guide plate 63, the collar member 64, the fixed drive pulley half 71, the cooling fan 65, and the washer 66 are sequentially inserted and inserted into the left shaft portion of the journal portion 40a of the left crankshaft 40L so as to be connected to the journal portion 40a. A fixed driving pulley half 71 is integrally attached to the left crankshaft 40L together with the cooling fan 65 so as to be rotated integrally with the left crankshaft 40L.

A spline groove is formed on the outer periphery of the cylindrical collar member 64, and a sliding support sleeve 68 is spline-fitted so that relative rotation is restricted and axial movement is possible. A cylindrical portion 72 s of the movable drive pulley half 72 is integrally fitted to the outer periphery of the sleeve 68.
Accordingly, the movable drive pulley half 72 is pivotally supported on the outer periphery of the collar member 64 that rotates integrally with the left crankshaft 40L via the sliding support sleeve 68 so as to be movable in the axial direction.

  The sliding support sleeve 68 to which the cylindrical portion 72s of the movable driving pulley half 72 is fitted has a portion extending leftward from the portion to which the cylindrical portion 72s is fitted, and an inner race is formed in the extended portion. 69i is fitted and a ball bearing 69 is provided.

  Between the inner peripheral surface of the cylindrical portion 71s of the fixed drive pulley half 71 and the outer peripheral surface of the cylindrical collar member 64, an annular recess 71h that opens to the right is formed, and the inner side of the cylindrical portion 71s. A conical coil spring 73 is inserted into the annular recess 71h.

  The conical coil spring 73 has a large-diameter left end in contact with the inner surface of the bottom wall portion 71b that extends inwardly of the left end of the cylindrical portion 71s, and a small-diameter right end that is fitted to the sliding support sleeve 68. The retainer 74 attached to the race 69i is in contact with the retainer 74, and the movable drive pulley half 72, which is sandwiched from the left and right sides and integrated with the sliding support sleeve 68, is urged away from the fixed drive pulley half 71.

  An endless V-belt 75 sandwiched between opposed tapered surfaces 71f and 72f facing each other between a fixed drive pulley half 71 and a movable drive pulley half 72 has an isosceles trapezoidal cross section and has an inner circumference so that it can be easily bent. The surface is wavy and irregularities are formed in the circumferential direction, and the height (thickness) of the trapezoid of the cross section of the V belt 75 at the convex portion 75p is large (see FIGS. 3 and 5).

Referring to FIGS. 4 and 5, a transmission case cover 61 that covers the left side of the V-belt type continuously variable transmission 60 is provided with a cooling air inlet 61 h that is largely open at the left side portion of the cooling fan 65.
In the cooling fan 65 that rotates integrally with the crankshaft 40, the outside air is introduced into the transmission chamber 60C from the cooling air introduction port 61h by the rotation of the plurality of blades 65p, and a part of the introduced outside air V The belt type continuously variable transmission 60 is cooled, and a part thereof enters forward from an opening 37bh of the air duct portion 37b of the shroud 37, and is guided by the air duct portion 37b to reach the cylinder block 32 and the cylinder head 33. The block 32 and the cylinder head 33 are cooled.

  When the engine speed is small, the force that moves the movable drive pulley half 72 to the left by the centrifugal force of the centrifugal weight 62 is small, and the force that biases the movable drive pulley half 72 to the right by the conical coil spring 73 The movable drive pulley half 72 is far away from the fixed drive pulley half 71, and the fixed drive pulley half 71 and the movable drive pulley half 72 sandwich the V belt 75 as shown in FIG. The V-belt 75 is supported on the outer race of the bearing 69 such that the convex portion 75p on the inner periphery is in contact with the outer race of the bearing 69.

Therefore, the V-belt 75 supported by the outer race of the bearing 69 does not transmit the rotation of the crankshaft 40 and is rotated without being sandwiched between the stationary driving pulley half 71 and the movable driving pulley half 72 rotating together with the crankshaft 40. Therefore, when the engine speed is small, the V-belt 75 does not circulate even if the drive pulley 70 rotates (see FIG. 5).

  When the engine speed increases, the force that moves the movable drive pulley half 72 to the left by the centrifugal force of the centrifugal weight 62 increases, and the force that biases the movable drive pulley half 72 to the right by the conical coil spring 73. The V belt 75 is moved between the rotating fixed driving pulley half 71 and the movable driving pulley half 72 by moving the movable driving pulley half 72 to the left and approaching the fixed driving pulley half 71. The V-belt 75 can be swung around and caught, and power can be transmitted to the rear driven pulley 80.

  When the engine speed increases greatly, the centrifugal force of the centrifugal weight 62 increases, and the movable drive pulley half 72 is further brought closer to the fixed drive pulley half 71 as shown in FIG. The winding diameter of the V belt 75 wound between the half body 71 and the movable driving pulley half body 72 increases, and accordingly, the winding diameter of the V belt 75 of the rear driven pulley 80 decreases. The ratio is automatically changed and continuously variable.

  On the other hand, a driven pulley 80 that is rotatably supported by a driven shaft 110 that is an input shaft of the reduction gear mechanism 120 behind the driving pulley 70 includes a first driven pulley half 81 that is slidable in the axial direction, and the first driven pulley half 81. And a second driven pulley half 82 facing on the right side.

  Referring to FIG. 4, driven shaft 110 extends to the right side of journal portion 110a that is pivotally supported through bearing 111 and sealed by seal member 112 at the rear portion of transmission case (left crankcase) 31L. A right extending shaft portion 110d is inserted into the reduction gear chamber 120C, and an end portion thereof is pivotally supported by the reduction gear cover 121 by a bearing 113.

In the reduction gear mechanism 120 in the reduction gear chamber 120C, a reduction intermediate shaft 122 is provided between the driven shaft 110 and the rear axle 125 so as to be parallel to each other (horizontal direction in the left and right directions), and a bearing is provided to the transmission case 31L and the reduction gear cover 121. It is supported by a shaft.
An intermediate large-diameter gear 123 fitted to the deceleration intermediate shaft 122 meshes with a small-diameter gear 111g formed on the driven shaft 110.

  The rear axle 125 is supported by a transmission case 31L and a reduction gear cover 121 via a bearing and protrudes to the right. A rear axle large-diameter gear 124 fitted to the rear axle 125 in the reduction gear chamber 120C is It meshes with a small-diameter gear 112g formed on the deceleration intermediate shaft 122.

The rear wheel 21 is fitted to a portion of the rear axle 125 protruding rightward from the reduction gear cover 121.
Therefore, the rotation of the driven shaft 110 is decelerated via the engagement of the small diameter gear 111g and the intermediate large diameter gear 123 of the reduction gear mechanism 120 and the engagement of the small diameter gear 122g and the rear axle large diameter gear 124 and is transmitted to the rear axle 125. As a result, the rear wheel 21 is rotated.

  Referring to FIG. 6, the left side of journal portion 110a of driven shaft 110 is reduced in diameter through a step so that spline shaft portion 110b extends into transmission chamber 60C, and the left end of spline shaft portion 110b is a male screw portion. 110c is formed.

  The spline shaft portion 110b of the driven shaft 110 includes a second pressed member 108, a ball bearing 107, and a cylindrical axially long collar member 106, in which three pressed pieces 108p radially extend from the inner peripheral base portion 108b. A first pressed member 105 (see FIGS. 2 and 3), in which three pressed pieces 105p extend radially from the inner peripheral base portion 105b, are sequentially spline-fitted, and a nut 109 is attached to the male screw portion 110c at the end of the spline shaft portion 110b. The first pressed member 105, the collar member 106, the ball bearing 107, and the second pressed member 108 are integrally attached to the driven shaft 110.

Note that a clutch shoe 105S, which is a friction member, is attached to the tip of the three pressed pieces 105p of the first pressed member 105 so as to protrude rightward.
Similarly, clutch shoes 108S, which are friction members, are attached to the front end portions of the three pressed pieces 108p of the second pressed member 108 so as to protrude leftward.
The first pressed member 105 and the second pressed member 108 have the same plane-symmetric shape.

An intermediate sleeve 102 is fitted on the outer periphery of a long cylindrical collar member 106 through a needle bearing 103 and a ball bearing 104 so as to be relatively rotatable.
In the intermediate sleeve 102, the large-diameter cylindrical portion 102a on the right side is fitted into the outer race of the needle bearing 103 and the ball bearing 104, and the small-diameter cylindrical portion 102b on the left side covers the outer periphery of the collar member 106 leaving the left end portion.

The first driven pulley half 81 and the second driven pulley half 82 have a first conical portion 81c and a second conical portion 82c that are opposed to each other and form opposing tapered surfaces 81f and 82f sandwiching the V belt 75, respectively.
The first driven pulley half 81 has a first inner peripheral cylindrical portion 81s that is bent to the right by bending an inner peripheral portion of the first conical portion 81c and an outer peripheral portion of the first conical portion 81c that is bent leftward. A first outer peripheral bent portion 81e is formed.
In the second driven pulley half 82, the inner peripheral portion of the second conical portion 82c is bent and the right inner peripheral cylindrical portion 82s extending rightward and the outer peripheral portion of the second conical portion 82c are bent rightward. A second outer peripheral bent portion 82e is formed.

A second support sleeve 84 fitted to the large-diameter cylindrical portion 102a of the intermediate sleeve 102 while allowing sliding is provided to cover the entire intermediate sleeve 102 and extend leftward.
Seal members 97a and 97b are interposed between the intermediate sleeve 102 and the second support sleeve 84 in the vicinity of the right end portion and the left end portion of the intermediate sleeve 102, respectively.

The second driven pulley half 82 is fitted to a second support flange portion 84 f formed at the right end of the second support cylindrical portion 84 s of the second support sleeve 84 at the end portion of the second inner peripheral cylindrical portion 82 s. .
Therefore, the second driven pulley half 82 is supported by the second support sleeve 84 and is pivotally supported while allowing the intermediate sleeve 102 to slide.

  An annular shape constituted by the inner peripheral surface of the second inner peripheral cylindrical portion 82s of the second driven pulley half 82, the outer peripheral surface of the second support cylindrical portion 84s of the second support sleeve 84, and the second support flange portion 84f. A second annular recess 82Q is formed to open to the first driven pulley half 81 side (left side).

A guide pin 85p protrudes in a radial direction and is fixed to a predetermined portion of the second support cylindrical portion 84s of the second support sleeve 84 corresponding to the small diameter cylindrical portion 102b of the intermediate sleeve 102.
A roller 85r is rotatably supported on a portion of the guide pin 85p that protrudes outward in the radial direction.

A first support sleeve 83 is fitted on the outer peripheral surface of the second support cylindrical portion 84s of the second support sleeve 84 so as to be capable of relative rotation and sliding in the axial direction.
Between the second support cylindrical portion 84 s of the second support sleeve 84 and the first support sleeve 83, seal members 98 a and 98 b are interposed near the right end portion and the left end portion of the first support sleeve 83, respectively.

  The first driven pulley half 81 is fitted to a first support flange portion 83f formed at the end portion of the first support cylindrical portion 83s of the first support sleeve 83 at the end portion of the first inner peripheral cylindrical portion 81s. The first support sleeve 83 and the second support sleeve 84 are pivotally supported integrally with the first support sleeve 83 so as to be slidable in both the circumferential direction and the axial direction.

  A cam hole 85h is spirally formed in the first support cylindrical portion 83s of the first support sleeve 83, and a guide pin 85p protruding from the second support cylindrical portion 84s of the second support sleeve 84 A torque cam mechanism 85 is configured by being slidably fitted into a spiral cam hole 85h via a roller 85r.

The first driven pulley half 81 and the second driven pulley half 82 having different rotational resistances are caused to rotate relative to each other by causing a difference in slippage from the V belt 75 such as during acceleration.
The torque cam mechanism 85 changes the relative rotation of the first driven pulley half 81 and the second driven pulley half 82 to an axial movement that brings them closer to each other by slidably fitting the guide pin 85p into the cam hole 85h. Thus, the V-belt 75 is sandwiched so that the rotating power of the V-belt 75 is reliably transmitted to the driven pulley 80 with as little slippage as possible.

  A shielding sleeve 86 is fitted to the outer peripheral surface of the first support cylindrical portion 83s of the first support sleeve 83, and a helical cam hole 85h formed in the first support cylindrical portion 83s of the first support sleeve 83 is shielded. It is shielded by the sleeve 86.

  The first support flange portion 83f at the end of the first support cylindrical portion 83s of the first support sleeve 83 has a diameter larger than that of the first support cylindrical portion 83s by the thickness of the shield sleeve 86, and the right end portion of the shield sleeve 86 is The annular shape between the first inner cylindrical portion 81s of the first driven pulley half 81 and the first support cylindrical portion 83s of the first support sleeve 83 until the first support sleeve 83 abuts on the first support flange portion 83f. It is inserted into the gap.

  The left end of the shielding sleeve 86 abuts on an annular collar member 87 regulated by a retaining ring 88 fitted in an outer peripheral groove formed on the outer peripheral surface of the left end portion of the first support cylindrical portion 83 s of the first support sleeve 83. The shielding sleeve 86 is externally fitted to the first support cylindrical portion 83 s of the first support sleeve 83 and attached integrally with the first driven pulley half 81.

An outer peripheral groove 86v is formed in the outer peripheral surface of the right end portion of the shielding sleeve 86 fitted into the first inner peripheral cylindrical portion 81s of the first driven pulley half 81, and a seal ring 89a is formed in the outer peripheral groove 86v. Are fitted.
Further, an outer peripheral groove 85v is formed on the left side of the cam hole 85h in the first support cylindrical portion 83s of the first support sleeve 83, and a seal ring 89b is fitted into the outer peripheral groove 85v.

  In the cam hole 85h of the first support cylindrical portion 83s of the first support sleeve 83 which is shielded by the shield sleeve 86, grease as a lubricant is stored so that the guide pin 85p slides easily. The seal ring 89a fitted in the outer peripheral groove 86v formed on the outer peripheral surface of the right end portion of the shielding sleeve 86 is a first inner peripheral cylinder of the first driven pulley half 81 so that the grease that has not leaked from the cam hole 85h. The seal ring 89b is pressed against the inner peripheral surface of the portion 81s and sealed, and the left end portion of the shielding sleeve 86 is fitted in the outer peripheral groove 85v formed in the first inner cylindrical portion 81s of the first driven pulley half 81. To prevent the grease accumulated in the cam hole 85h of the first support cylindrical portion 83s from leaking left and right from the cam hole 85h.

  The cam hole 85h formed in the first support cylindrical portion 83s of the first support sleeve 83 is formed up to the axial position where the outer peripheral groove 86v formed in the outer peripheral surface of the right end portion of the shielding sleeve 86 exists. (See FIG. 8).

The first inner peripheral cylindrical portion 81s of the first driven pulley half 81 has an outer diameter smaller than the inner diameter of the second inner peripheral cylindrical portion 82 and extends in the axial direction toward the second driven pulley half (right side). The first annular convex portion 81P is formed together with the first support flange portion 83f fitted to the first support sleeve 83.
The first annular convex portion 81P faces the second annular concave portion 82Q inside the second inner peripheral cylindrical portion 82s of the second driven pulley half 82, and can be inserted into the second annular concave portion 82Q (see FIG. 6).

A sliding support sleeve 90 is slidably attached to the inside of the left end portion of the second support cylindrical portion 84 s of the second support sleeve 84 by spline fitting, leaving the left end portion. The first pressing member 91 is fitted on the outer periphery of the left end exposed from the support cylindrical portion 84s.
In the first pressing member 91, five spoke portions 91s radially extending from a hub portion 91h fitted to the sliding support sleeve 90 integrally support the annular pressing portion 91p at the tip (FIG. 3). FIG. 6).

  The first pressing member 91 is disposed to face the right side of the first pressed member 105, and the outer diameter of the annular pressing portion 91 p of the first pressing member 91 is the inner peripheral base portion of the first pressed member 105. It is substantially equal to the outer diameter of the three pressed pieces 105p extending radially from 105b.

  Since the sliding support sleeve 90 that supports the first pressing member 91 is spline-fitted inside the second supporting cylindrical portion 84s of the second supporting sleeve 84, the first pressing member 91 slides in the axial direction. Thus, the first pressed member 105 can be moved closer to or away from the first pressed member 105.

When the first pressing member 91 slides to the left and approaches the first pressed member 105, the annular pressing portion 91p of the first pressing member 91 is at the tip of the pressed piece 105p of the first pressed member 105. Pressed by the attached clutch shoe 105S, the rotation of the first pressing member 91 is transmitted to the first pressed member 105, the first pressing member 91 slides to the right, and the first pressing member 91 is the first. When separated from the pressed member 105, the annular pressing portion 91p loses the force to press the clutch shoe 105S, and the rotation of the first pressing member 91 is not transmitted to the first pressed member 105.
As described above, the first dry clutch mechanism C <b> 1 is configured between the first pressing member 91 and the first pressed member 105.

On the other hand, on the second driven pulley half 82 side of the driven pulley 80, an annular disk-shaped second pressing member 92 is fixed to the end surface of the second outer peripheral bent portion 82e of the second driven pulley half 82 at the outer peripheral portion. Is provided.
The second pressed member 108 that is in contact with the journal portion 110a of the driven shaft 110 and is fixed to the driven shaft 110 is positioned opposite to the right side of the second driven pulley half 82, and is outside the three pressed pieces 108p. The diameter is substantially equal to the outer diameter of the second driven pulley half 82.
A clutch shoe 108S attached to the tip of the three pressed pieces 108p of the second pressed member 108 faces the second pressing member 92 fixed to the second driven pulley half 82.

When the second driven pulley half 82 slides to the right and approaches the second pressed member 108, the second pressing member 92 is attached to the tip of the pressed piece 108p of the second pressed member 108. Pressed by the shoe 108S, the rotation of the second pressing member 92 is transmitted to the second pressed member 108, the second pressing member 92 slides to the left, and the second pressing member 92 becomes the second pressed member 108. When the distance from the second pressing member 92 is increased, the force by which the second pressing member 92 presses the clutch shoe 108S is lost, and the rotation of the second pressing member 92 is not transmitted to the second pressed member 108.
As described above, the second dry clutch mechanism C <b> 2 is configured between the second pressing member 92 and the second pressed member 108.

The five spoke portions 91s of the first pressing member 91 constituting the first dry clutch mechanism C1 are formed with an annular bent portion 91ss bent rightward at a predetermined radius portion in the radial direction. The retainer 94 is held by being gripped by the five bent portions 91ss formed.
The retainer 94 is formed with a conical portion 94a having a diameter gradually reduced to the right from a large-diameter spring receiving portion 94c held at the bent portion 91ss of the five spoke portions 91s. The right end of the small diameter is slightly extended inward to form a reduced diameter annular portion 94b having a circular opening.

The reduced diameter annular portion 94b at the right end of the retainer 94 can pass through the circular opening of the shielding sleeve 86 integral with the first driven pulley half 81, and the annular collar member 87 at the left end of the shielding sleeve 86 is the reduced diameter annular portion. It is always on the left side of 94b.
A conical coil spring 95 is interposed between the spring receiving portion 94c at the left end of the retainer 94 and the first inner peripheral cylindrical portion 81s at the inner peripheral edge of the first conical portion 81c of the first driven pulley half 81.

The large-diameter left end of the conical coil spring 95 is brought into contact with the spring receiving portion 94c of the retainer 94, and the small-diameter right end is in contact with the shielding sleeve 86 of the first inner peripheral cylindrical portion 81s of the first driven pulley half 81. Abutted.
Therefore, the conical coil spring 95 biases the first pressing member 91 and the first driven pulley half 81 in a direction away from each other via the retainer 94.

  Note that the conical coil spring 95 urges the first pressing member 91 to the left opposite to the second driven pulley half 82 to make the first pressing member 91 the first pressed member of the first dry clutch mechanism C1. 105, and the conical coil spring 95 biases the second driven pulley half 82 to the right opposite to the first driven pulley half 81, and the second driven pulley half via the V belt 75. The second pressing member 92 and the second pressing member 92 are urged to the right to approach the second pressed member 108 of the second dry clutch mechanism C2.

  When the engine speed is small and the winding diameter of the V-belt 75 wound between the first driven pulley half 81 and the second driven pulley half 82 is the largest, the first driven pulley half 81 and the second driven pulley half 81 The two driven pulley halves 82 approach each other, the first annular protrusion 81P on the first driven pulley half 81 side is inserted into the second annular recess 82Q on the second driven pulley half 82 side, and the conical coil spring The spring force of 95 is hardly working, and both the first dry clutch mechanism C1 and the second dry clutch mechanism C2 are in a disconnected state (see FIG. 6).

  As the engine speed increases, the winding diameter of the V-belt 75 between the first driven pulley half 81 and the second driven pulley half 82 is reduced, and the first driven pulley half 81 and the second driven pulley are reduced. When the half bodies 82 are separated from each other, the first pressing member 91 and the second pressing member 92 are moved away from each other via the V-belt 75 and the conical coil spring 95, so that the first pressing member 91 is the first pressed member. 105, the annular pressing portion 91p of the first pressing member 91 contacts the clutch shoe 105S of the first pressed member 105, and at the same time, the second pressing member 92 approaches the second pressed member 108, and the second pressing member 92 Is brought into contact with the clutch shoe 108S of the second pressed member 108, and further, when the conical coil spring 95 is compressed and a spring force is applied, the first pressing member 91 becomes the clutch shoe 105S of the first pressed member 105. To connect the first dry clutch mechanism C1 and simultaneously Pressing member 92 connects the second dry clutch mechanism C2 to press the clutch shoe 108S of the second pressed member 108 (see FIG. 8).

  Due to the connection of the first dry clutch mechanism C1 and the second dry clutch mechanism C2, the rotation of the driven pulley 80 due to the rotation of the V belt 75 is transmitted to the driven shaft 110, and the rotation of the driven shaft 110 is transmitted via the reduction gear mechanism 120. The motorcycle 1 travels as the rear wheel 21 is rotated by being transmitted to the axle 125.

In the V-belt type continuously variable transmission 60 as described above, the movement of the front driving pulley 70 according to the engine speed and the movement of the rear driven pulley 80 via the V belt 75 are related to each other in FIGS. 8 will be briefly described.
5 and 6 show the state of the driving pulley 70 and the state of the driven pulley 80 of the V-belt type continuously variable transmission 60 when the engine speed is small.

  When the engine speed is low, such as during idle operation, the movable pulley half 72 is fixed on the drive pulley 70 side by the spring force of the conical coil spring 73, which is greater than the centrifugal force of the centrifugal weight 62, as shown in FIG. The V-belt 75 is largely separated from the driving pulley half 71 and is supported by the outer race of the bearing 69 without being sandwiched between the rotating fixed driving pulley half 71 and the movable driving pulley half 72. The belt 75 does not go around.

  In the state of the drive pulley 70 side, the V belt 75 is wound around the bearing 69 and the winding diameter is the smallest. Therefore, on the driven pulley 80 side, as shown in FIG. The winding diameter of the V belt 75 wound between the second driven pulley half 82 is the largest, the V belt 75 does not circulate, and the spring force of the conical coil spring 95 hardly acts. Both the first dry clutch mechanism C1 and the second dry clutch mechanism C2 are in a disconnected state.

  Therefore, when the engine speed is small, such as during idling, the power of the internal combustion engine 30 is transmitted only to the crankshaft 40 and does not involve the revolving motion of the V-belt 75 or the rotation of the driven pulley 80. It is possible to reduce the load and improve fuel efficiency.

7 and 8 respectively show the state of the driving pulley 70 and the state of the driven pulley 80 of the V-belt type continuously variable transmission 60 when the engine rotation is large.
When the engine speed increases, the movable pulley half 72 is moved to the left by the centrifugal force of the centrifugal weight 62, which exceeds the spring force of the conical coil spring 73, on the drive pulley 70 side, as shown in FIG. The V-belt 75 is sandwiched between the rotating fixed driving pulley half 71 and the movable driving pulley half 72 which is brought close to the fixed driving pulley half 71 and the movable driving pulley half 72 is rotated. Power can be transmitted to the rear driven pulley 80 while increasing the winding diameter of the V belt 75 wound between the movable driving pulley half 72.

  The V belt 75 that circulates while enlarging the winding diameter of the V belt 75 around the drive pulley 70 is on the driven pulley 80 side, as shown in FIG. 8, the first driven pulley half 81 and the second driven pulley half. The first driven pulley in the direction in which the first driven pulley half 81 and the second driven pulley half 82 are moved away from each other in a direction in which the first driven pulley half 81 and the second driven pulley half 82 move away from each other. The half body 81 and the second driven pulley half body 82 are connected to the first pressing member 91 and the second pressing member 92 via the V belt 75 and the conical coil spring 95, respectively, and the first pressed member 105 and the second pressed member 108, respectively. And the first pressing member 91 and the second pressing member 92 press the clutch shoe 105S of the first pressed member 105 and the clutch shoe 108S of the second pressed member 108. The first dry clutch mechanism C1 and the second dry clutch mechanism C2 are simultaneously connected. The rotation of the driven pulley 80 due to the rotation of the V-belt 75 is transmitted to the driven shaft 110 via the first dry clutch mechanism C1 and the second dry clutch mechanism C2 connected to the rear wheel 21 via the reduction gear mechanism 120. Is transmitted to.

As described above, the embodiment of the V-belt continuously variable transmission according to the present invention described in detail has the following effects.
As shown in FIG. 5, the drive pulley 70 is provided with a conical coil spring 73 that urges the movable drive pulley half 72 in a direction away from the fixed drive pulley half 71, and the engine speed is low. The movable drive pulley half 72 is largely separated from the fixed drive pulley half 71 by the spring force of the conical coil spring 73, which exceeds the centrifugal force of the centrifugal weight 62, and the V-belt 75 is movable with the rotating fixed drive pulley half 71. Since it is supported by the outer race 69o of the bearing 69 without being sandwiched between the drive pulley halves 72, the V belt 75 does not circulate even if the drive pulley 70 rotates.

  Therefore, when the engine speed is small, such as during idling, the V-belt 75 does not rotate without rotating between the stationary driving pulley half 71 and the movable driving pulley half 72 that rotate with the crankshaft 40 and without rotating. The power of the internal combustion engine 30 can only be transmitted to the crankshaft 40, and it can be prevented from rotating around the V belt 75 and the driven pulley 80, reducing the load during idling and improving fuel efficiency. Can be achieved.

  As shown in FIG. 5, the movable drive pulley half 72 is fitted on a sliding support sleeve 68 that is supported by the crankshaft 40 so as to be slidable in the axial direction with relative rotation restricted. A bearing 69 is fitted on the outer periphery of the extended portion of the sleeve 68 extending toward the fixed drive pulley half 71 in the axial direction from the movable drive pulley half 72, and the bearing 69 is fixedly driven when the engine speed is low. Since it is located between the pulley half 71 and the movable drive pulley half 72, when the engine speed is low, the V-belt 75 is fitted to a sliding support sleeve 68 that rotates integrally with the crankshaft 40. The friction between the sliding support sleeve 68 and the V-belt 75, which are supported by the outer race 69o and rotate, can be suppressed, and the fuel consumption can be further improved.

  As shown in FIG. 5, the conical coil spring 73 is inserted into the cylindrical portion 71s of the fixed drive pulley half 71 and interposed between the bottom wall portion 71b and the movable drive pulley half 72. The conical coil spring 73 is compactly disposed in the cylindrical portion 71s that overlaps the conical portion 71c that forms the opposed tapered surface 71f of the fixed drive pulley half 71 in the axial direction, and the axial width of the drive pulley 70 can be kept small. Thus, the power unit 20 can be reduced in size.

  As shown in FIGS. 5 and 7, the conical coil spring 73 can increase the expansion / contraction stroke by overlapping in the axial direction when the spring is compressed, compared to a normal coil spring having the same diameter spiral. In addition, the axial width of the drive pulley 70 can be kept small.

  As shown in FIG. 5, the conical coil spring 73 is sandwiched between the bottom wall 71b of the fixed drive pulley half 71 and the inner race 69i of the bearing 69 and rotates together with the crankshaft 40, so the engine speed is small. Sometimes, the rotation of the fixed drive pulley half 71 can be reliably prevented from being transmitted to the V belt 75 supported by the outer race 69o of the bearing 69.

  As shown in FIG. 7, when the engine speed increases, the bearing 69 moves to the inside of the cylindrical portion 71 s of the fixed drive pulley half 71 due to the movement of the movable drive pulley half 72 toward the fixed drive pulley half 71. Therefore, the axial width of the drive pulley 70 can be kept as small as possible while securing the moving distance of the movable drive pulley half 72, and the power unit 20 can be further miniaturized.

  The V-belt type continuously variable transmission according to the embodiment of the present invention has been described above. However, the aspect of the present invention is not limited to the above-described embodiment, and various aspects are within the scope of the gist of the present invention. Including what is implemented in.

  For example, the vehicle of the present invention is not limited to the straddle-type motorcycle 1 of the embodiment, but may be a variety of straddle-type vehicles such as a scooter type, a three-wheel, and a four-wheel buggy. Any vehicle having the requirements may be used.

DESCRIPTION OF SYMBOLS 1 ... Motorcycle, 20 ... Power unit, 30 ... Internal combustion engine, 40 ... Crankshaft,
60 ... V belt type continuously variable transmission, 62 ... centrifugal weight, 63 ... guide plate, 64 ... collar member, 68 ... sliding support sleeve, 69 ... ball bearing,
70 ... Drive pulley, 71 ... Fixed drive pulley half, 71c ... Conical part, 71s ... Cylindrical part, 71b ... Bottom wall part, 72 ... Movable drive pulley half, 72c ... Conical part, 72s ... Cylindrical part, 73 ... Conical Coil spring, 74 ... Retainer, 75 ... V belt,
80 ... driven pulley, 81 ... first driven pulley half, 82 ... second driven pulley half, 83 ... first support sleeve, 84 ... second support sleeve, 85 ... torque cam mechanism, C1 ... first dry clutch mechanism, C2: Second dry clutch mechanism,
110: Driven shaft.

Claims (4)

Between the drive pulley (70) provided on the drive shaft (40) to which the power of the in-vehicle internal combustion engine is transmitted and the driven pulley (80) provided on the driven shaft (110) to which the power is transmitted to the wheels, V A belt (75) is laid,
The drive pulley (70) is configured such that a movable drive pulley half (72) supported by the drive shaft (40) so that relative rotation is restricted and slidable in the axial direction is axially dependent on the engine speed. Opposing taper surfaces (71f, 72f) facing each other between the fixed drive pulley half (71) that slides and is fixed to the drive shaft (40) circulate around the V belt (75). In the V-belt continuously variable transmission that transmits power to the driven shaft (110),
Biasing means (73) for urging the movable drive pulley half (72) in a direction away from the fixed drive pulley half (71) is provided ,
The biasing means (73) is a conical coil spring (73),
The fixed drive pulley half (71) is axially aligned with the movable drive pulley half (72) from the inner peripheral end of the conical portion (71c) to the conical portion (71c) forming the opposed tapered surface (71f). A cylindrical portion (71s) extending to the opposite side, and a bottom wall portion (71b) that is fixed to the drive shaft with the end opposite to the conical portion (71c) of the cylindrical portion (71s) extending inward And
The conical coil spring (73) is inserted into the cylindrical portion (71s) of the fixed drive pulley half (71), and between the bottom wall portion (71b) and the movable drive pulley half (72). A V-belt type continuously variable transmission which is interposed in Between the drive pulley (70) provided on the drive shaft (40) to which the power of the in-vehicle internal combustion engine is transmitted and the driven pulley (80) provided on the driven shaft (110) to which the power is transmitted to the wheels, V A belt (75) is laid,
The drive pulley (70) is configured such that a movable drive pulley half (72) supported by the drive shaft (40) so that relative rotation is restricted and slidable in the axial direction is axially dependent on the engine speed. Opposing taper surfaces (71f, 72f) facing each other between the fixed drive pulley half (71) that slides and is fixed to the drive shaft (40) circulate around the V belt (75). In the V-belt continuously variable transmission that transmits power to the driven shaft (110),
Biasing means (73) for urging the movable drive pulley half (72) in a direction away from the fixed drive pulley half (71) is provided ,
The biasing means (73) is a coil spring (73);
The fixed drive pulley half (71) is axially aligned with the movable drive pulley half (72) from the inner peripheral end of the conical portion (71c) to the conical portion (71c) forming the opposed tapered surface (71f). A cylindrical portion (71s) extending to the opposite side, and a bottom wall portion (71b) that is fixed to the drive shaft with the end opposite to the conical portion (71c) of the cylindrical portion (71s) extending inward And
The coil spring (73) is inserted into the cylindrical part (71s) of the fixed drive pulley half (71), and between the bottom wall part (71b) and the movable drive pulley half (72). Intervened,
The movable drive pulley half (72) is fitted to a sliding sleeve (68) that is supported by the drive shaft (40) so that relative rotation is restricted and slidable in the axial direction.
A bearing (69) is fitted on the outer periphery of the extending portion of the sliding support sleeve (68) extending in the axial direction from the movable drive pulley half (72) toward the fixed drive pulley half (71). ,
The V-belt , wherein the bearing (69) is positioned between the fixed drive pulley half (71) and the movable drive pulley half (72) when the engine speed is low. Type continuously variable transmission. The coil spring (73) is interposed between the bottom wall (71b) of the fixed drive pulley half (71) and an inner race (69i) of the bearing (69). The V-belt type continuously variable transmission according to claim 2 . Said movable driving pulley half due to the fact that the engine speed increases above during approach movement of the fixed driving pulley half to (71), said bearing (69) is the fixed driving pulley half (72) (71) The V-belt type continuously variable transmission according to claim 3 , wherein the cylindrical portion (71s) is provided so as to be accommodated inside the cylindrical portion (71s) .

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